Name: Nobuhiko Akizuki
Designation: Century King Shadow Moon
Weapons: Satan Saber
Gear: King Stone
Nobuhiko Akizuki was born on the day of a solar eclipse alongside his stepbrother Kotaro Minami, revered by the Gorgom as the heirs to their leader's throne: the Century Kings "Shadow Moon" and "Black Sun". Raised together, the two were like brothers. Once the two were of the ideal age, Gorgom captured them and infused them each with a King Stone. While Kotaro manages to escape, Nobuhiko is left in a state of suspended animation before being finally reborn as Shadow Moon through the Stones of Land, Heaven, and Sea.. Shadow Moon sets up his regime as a general of Gorgom, serving as Black's nemesis and forcing him to fight him so he can become the new Creation King. In their final battle, Shadow Moon is weakened by Kamen Rider Black after the Satan Saber is used to slash his King Stone. Though he appears to die after being left inside the Gorgom headquarters when it explodes, Shadow Moon returns years later to seek revenge against Kotaro Minami, Black RX. He is finally defeated by Black RX when the Revolcane is thrust through Shadow Moon's King Stone, destroying it once more. He turns back into Nobuhiko, renouncing his evil ways as he saved Shigeru and Hitomi, shortly before he dies. The King Stone is Shadow Moon's transformation belt. Embedded upon the center his belt is a green stone called the Stone of the Moon. Through this stone, Shadow Moon can telepathically communicate with Kotaro via his own King Stone. The Satan Saber is a weapon created for use by the Century Kings. Though Bilgenia took it, Shadow Moon reclaimed the weapon and took it as his own. Though he lost it to Black during their final battle, Shadow returns during Black RX with the twin Shadow Sabers.